CHAPTER XVIII

  Savage Tribesmen

  For a moment the youths were taken completely aback in surprise. Thatthey would see anything like this away out on the Sahara was not inthe least expected. They stood for some time in sheer amazement andnot a little fear.

  "An army coming at us!" muttered Bob, staring at the distantspectacle.

  "An army, yes. Must be five hundred cavalrymen."

  "But--but it can't be! It's impossible. What would soldiers be doingaway out here on the desert? Something's seriously wrong somewhere. Ifjust one of us should see such a thing it might indicate that the oldbrain wasn't working just right, but for you and I both----"

  "Come on," suggested Joe, giving his dromedary a slight kick. "Let'sget out of here. I'm greatly worried."

  The youths turned their camels back to camp for a short distance; thenthey urged them on to a fast trot.

  They were not a little relieved when they finally reached the oasis,where they found their friends awaiting them.

  "Where have you been so long?" inquired Mr. Lewis, his face not alittle serious.

  "We thought maybe something held you back," added Dr. Kirshner.

  "It did," replied Bob, trying to remain calm.

  The men sat up quickly, sensing that some misfortune had come upon theboys.

  "What was it?" demanded Mr. Holton tensely.

  "An army," Joe returned soberly.

  For a second there was silence. Then the men broke out in laughter.Evidently they thought the youths were joking. Even Fekmah joined in,his dark features drawn together in mirth.

  "Nothing to laugh at," said Joe, vexed because the men thought theirexperience funny. "It nearly scared Bob and me out of our wits."

  Mr. Holton grew more serious.

  "Come, now," he said. "Tell us what you mean."

  Joe told of seeing the phenomenon from the top of the hill, sayingthat there appeared to be at least five hundred horsemen coming towardthem.

  When he had finished, the naturalists and Dr. Kirshner jumped up inwonder and not a little fear, but Fekmah only laughed.

  "W-what's humorous!" demanded Mr. Lewis, greatly perplexed.

  "Everything," said Fekmah, laughing still harder. "What the young mensaw was only an illusion or mirage. There no army on Sahara. Only looklike army."

  "You mean it was a trick of nature, like the more common mirages oflakes on the desert?" asked Dr. Kirshner with great interest.

  "Yes," the Arab answered. "Caused by the bending of the rays of lightwhen they strike the hot sand."

  "Well, that's a new one on me!" confessed Bob. "I was aware of thefact that mirages of lakes are common, but that I should see anarmy----"

  It was now rapidly becoming dark. The explorers thought it best tosleep all through the night and not wait for the moon, for theygreatly needed the rest.

  "Tomorrow morning I'd like to see that mirage that you boys thoughtwas an army," said Mr. Holton, when they prepared to retire.

  "And I, too," put in Dr. Kirshner. "As it isn't out of our way, we canall ride over there."

  "It'll be a good chance to take some motion pictures," said Bob. "Ascene as unusual as that is sure to attract the curiosity of anaudience."

  Tishmak informed them that they would be out of this short sandstretch early the next morning. Then they would come into the AhaggarMountains, the real home of the mysterious Tuaregs.

  "And I expect to begin my work in this region," announced Dr.Kirshner. "Perhaps if I put legend and history together, I can locatesomething that will prove of great value to the world of archaeology. Ihave in mind at present the tomb of a great king who reigned in thosemountains many thousands of years ago. He is said to be an ancestor ofthe Berbers, who are related to the Tuaregs. When we come to the manyTuareg villages, I intend to make inquiries as to their ancientlegends."

  They were up early the next morning, anticipating the exploration ofthe mountains that lay ahead of them.

  But in order to get to the Ahaggars, it would be necessary to continuefor a short distance over the sand dunes.

  After breakfast they rode over to the distant hill to get a view ofthe mirage seen by the boys the day before. Sure enough, the army ofhorsemen appeared to be riding toward them, and the details wererather plain.

  Mr. Lewis shook his head in bewilderment.

  "Sure is strange," he muttered. "Why should the horses and the ridersbe so clearly defined? I can easily understand the mirage of a lake,but this sure gets my goat."

  They stood for some time staring at the distant spectacle, Bob and Joetaking motion pictures. Finally they rode on up the hill to catch aglimpse of the Ahaggars.

  "I rather think that peak not Illiman but Oudane," said Fekmah to theyouths, in answer to their question asking the name of the distanthigh mountain. "Mount Oudane very high, and much nearer than MountIlliman."

  More movies were taken by the youths. Then they rode down the oppositeside of the dune in the direction of the mountains.

  "Ahaggars very strange," said Fekmah to the Americans, as they rode ina group at the back of their pack camels. "There are high cliffs, tallneedle-like peaks, deep caves. There are canyons, ravines, undergroundpassageways. We see much, and we too be in great danger."

  "Danger?" Joe looked up in some surprise.

  "Yes. Very great danger. Wild Tuaregs roam about, and when on a raid,think only of robbing travelers. Then, too, we be in region where thetwo thieves who stole my map are. They perhaps be waiting for us andshoot us quick without giving warning. Many other dangers we mightsee."

  Fekmah sobered the Americans a little. They had not anticipated anygreat peril, although they knew the two thieves might, should theyhave arrived at the hidden riches first, give them trouble.

  "But we'll come out all right," predicted Bob, again becomingcheerful. "We'll show those fellows that we're capable of attendingto any crisis."

  A little farther on they reached the wall of rock that had previouslyshut out the view of the mountains. It stretched many miles to theirright and left, but there were numerous breaks that afforded openingsinto the country beyond.

  They had barely reached the other side of the wall-like formation whenJoe caught sight of a group of tents quite a distance to the east. Hemotioned for his friends to look in that direction.

  "Probably Arabs," pronounced Fekmah, after Tishmak had chatteredrapidly for a moment. "They nomads, who wander about the desert takingtheir flock of goats with them."

  "Suppose we go over and see them," suggested Mr. Holton. "Perhaps theycan give us a description of the country ahead of us. There may bemany more wells than we think, and it will do us no harm to know ofthem."

  The others were in favor of carrying out Mr. Holton's move. But Fekmahwarned them to be on the lookout for treachery.

  "They probably not do us harm, but can never tell," he said, as thedromedaries were turned in the direction of the tents.

  They reached the encampment in a very short time and were about tolook up some of the Arabs when a savage growl made them wheel aroundin surprise and fear.

  "Look!" cried Joe, laying his hand on his rifle.

  Two large, savage dogs were making toward them with all fury, showingtheir terrible teeth in anger. The enraged creatures were probablyowned by the Arabs in the tents and were acting as guards against allmarauders.

  The foremost dog was almost upon Mr. Lewis's camel. In another momentthe beast would sink its teeth in the dromedary's throat.

  Displaying the quickness of a cat, the naturalist unslung his rifle,took hasty aim, and fired.

  The report of the gun was followed by a longdrawn howl from the hugedog.

  "Quick!" cried Bob. "The other dog!"

  The second beast was rushing forward angrily.

  Mr. Lewis again took aim. The others, trusting in his marksmanship,made no move to get their rifles.

  Click! There was no report this time. His magazine was empty!

  Mr. Holton tried vainly to get his ri
fle out in time. Something mustbe done at once, for the savage dog would be at the camels in but amoment.

  Suddenly Joe leaped from his camel directly in the path of theoncoming animal. The dog stopped for a second, then rushed at theyouth with terrible ferocity.

  "It's now or never!" Joe thought and brought the butt of his rifledown with all his strength on the dog's head.

  There was a cry of pain, and the next moment the beast rolled over ina dazed condition. At last the terrible enemies had been overcome.

  "Great work, Joe!" praised Mr. Holton. "We weren't expecting to seeyou act so quickly."

  "I didn't know whether I could hit him at the right time or not," theyouth said, wiping the perspiration from his brow. "But I thought I'dtake a chance. It----"

  He stopped fearfully as a rifle shot rang out. Another report followedthe first, and Tishmak fell from his dromedary.

  "Back!" cried Dr. Kirshner. "It's the Arabs shooting from the tents.Hurry or we'll all be hit!"

  Tishmak was rapidly picked up and placed on his camel, and then theexplorers retreated behind a formation of rock near the high wall ofstone that was to their right.

  "You look after Tishmak," said Mr. Holton to Dr. Kirshner. "Meanwhilewe'll keep these Arabs away. We certainly aroused their tempers whenwe put those dogs out."

  A volley of shots came from the Arabs' tents, and the Americans atonce answered with their own rifles. Wherever a shot was heard, Mr.Holton directed his friends to fire at the spot.

  Suddenly Mr. Lewis caught a glimpse of a large one-armed Arab whoemerged into full view to send a bullet at his white enemies. Withouthesitation the naturalist fired, bringing the man down with a thud.

  "Look!" cried Bob. "They're backing up. That fellow you shot must havebeen the leader."

  "Does seem that way," agreed Mr. Lewis. "But we must remain on guard.These are treacherous characters."

  Only an occasional shot rang out. Then finally there was silence.

  "Now we'll see how Tishmak is," said Mr. Holton, leaving his positionat the end of the rocky crag.

  They found that Dr. Kirshner had bound and treated the wound, whichwas in the left arm. The Arab seemed in high spirits, despite the factthat he was evidently in pain.

  "It doesn't appear serious," said the archaeologist. "With the rightkind of attention it will probably be all right in a few days."

  "Lucky that he wasn't killed, or that more of us weren't hit,"remarked Mr. Lewis gravely. "The Sahara is a dangerous place forexplorers."

  They waited several minutes for any more rifle shots from the Arabs,but none came. Finally Mr. Holton mounted his dromedary.

  "Let's get on our way," he suggested. "I don't think there's anydanger now. The Arabs have retreated to a distance beyond theirtents, and I believe they'll stay there awhile."

  Tishmak was helped on his camel. Then, when the others had alsomounted, they rode off.

  They were now rapidly leaving the region of low sand dunes behind.Rocks of all sizes and shapes became more numerous, and vegetation wasmore abundant. There were, however, stretches of coarse sand plains,which were now and then dotted with boulders.

  Suddenly, as they ascended a long low hill, Bob and Joe cried out indelight and pointed to something a half-mile or so away.

  "A lake!" exclaimed Joe happily. "A lake of water!"